Cage construction for electron discharge devices



y 6, 1955 s. R. BEARD, JR 3,193,716

CAGE CONSTRUCTION FOR ELECTRON DISCHARGE DEVICES Filed April 5, 1962 INVENTOR! SAMUEL R. BEARDMR.

3,193,716 CAGE CDNSTRUQTION FUR ELECTRQN DISCHARGE DEVECES Samuel R. Beard, (in, Gwcnshoro, Ky, assignor to General Electric Company, a corporation of New York Filed Apr. 5, 1%2, Ser. No. 185,261 6 Claims. (Ql. 3ll3--l) This invention relates to a mount assembly for electron discharge devices and, in particular, to an assembly for mounting .a plurality of electron discharge devices within a single envelope.

In the manufacture and use of electron discharge devices it has been found to be advantageous to mount several complete electron discharge devices within a single envelope for purposes of economy of construction, operation, and space. Such structures require that the individual electron discharge devices and the various electrodes of each be arranged in closely spaced relation. The electrode elements of the electron discharge devices are normally supported between spaced insulators such as laminated mica disks by insertion of the end portions of the electrode elements into suitably located apertures in the spaced insulators, to thereby maintain the electrode elements in spaced relation.

Several problems arise in the manufacture of an electron tube of the type in which several electron discharge devices are contained within the tube envelope. The necessary close spacing of the individual electron discharge devices and their respective electrodes requires that a relatively large number of accurately located, punched apertures be made in small area mica disks so as to receive the end portions of the electrode elements. Mica tends to dc-laminate when pierced and the tendency is increased in proportion to the number of holes punched in a given mic-a disk. Thus, a large number of aper tures mechanically weakens the mica supports, and, further, requires complex dies for their formation.

A problem also arises in the mechanical operation of inserting the end portions of the electrode elements into the proper locating apertures in the mica disks. Each of the electrode elements, as for example, the cathode, plate, grids, usually requires at least two tabs,ears, or legs, at least one of which is at each end of the electrode element, for support and alignment. When a large number of electrode elements are employed in a limited space, it becomes very diflicult to thread the plurality of tabs, ears, or legs through the apertures in the mica supports.

The diificul-ty is aggravated when the mounting of the electrode elements is eiiected by mechanized or automated means, since all the elements must be carefully aligned and held while the apertured mica supports are secured to the electrode elements. Also, the aligning tools must remain in alignment with respect to the mica supports while being withdrawn from the assembled unit, otherwise a force will be exerted on the mica supports tending to de-laminate them. Mechanized equipment designed for assembly of prior art mount structures becomes very complica-ted and its complexity increases with the number of electrodes in a given structure. When double pentode type electron discharge devices are mounted within a single envelope, the mechanized equipment required for assembly may become prohibitively complicated.

It is an object of the invention to provide an improved assembly for mounting a plurality of electron discharge devices within a single envelope.

It is another object of the invention to provide a simplified assembly for mounting a plurality of electron discharge devices within a single envelope which facilitates the mounting of electrodes between support elements.

In accordance with the illustrated embodiment of the Edd-3,716

Fermented July 6, 1965 Tree invention, each of the electron discharge devices to be incorporated into a single envelope is individually mounted on respective insulative supports which are apert'ured to receive the ends of the electrode elements. A metallic member, which conveniently is a part of the active anode of one device, is utilized to interconnect the respective electron discharge devices. The member is shaped so as to be adaptable for ready attachment to each of the individual electron discharge devices, thereby serving to integrate the individual electron discharge devices into a single unit. The insulative supports of the individual electron discharge devices are shaped so as to be complementary so that, upon assembly into a unit, the periphery of the insulative support combination corresponds generally to the shape of the inside wall of the envelope so as to aid in supporting the unit within the envelope.

The subject matter of the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention, however, may best be understood by reference to the following description taken in connection with the accompanying drawing, in which:

FIG. 1 is an exploded perspective view of the mount assembly of the invention;

FIG. 2 is an enlarged side view illustrating the assembly of the individual electron discharge devices into an integral unit by means of the interconnecting member; and

FIG. 3 .is a partially cut-away isometric view of a tube incorporating the mount assembly of the invention.

With reference to FIG. 1, the mount assembly of the invention utilizes a member lid, which as will appear, functions as part of the anode of one device, and operates to interconnect the respective electron discharge devices ill and 12 to each other and to integrate them into a rigid unit. The planar main element 13 of member It has flanges 1d and 15 which are either integrally formed with main element 13 or attached thereto. The flanges l4 and 15 extend in generally parallel planes perpendicular to the plane of main element 13. Main element 13 has cars 17 extending from its top and. bottom edges while flanges l4 and 15 have cars 18 extending from the top and bottom edges respectively.

Electron discharge device 11, which, in the illustrative embodiment here to be described, is a pentode and includes a pair of spaced insulative supports 20 and 21, which may be in the form of mica segments, each having a plurality of apertures formed therein. The various electrodes of the electron discharge device are adapted to be supported and maintained in spaced relation between the mica supports by virtue of the engagement of the ends of the electrodes in the apertures formed in the mica sup' ports. In assembled condition, the end of cathode 22 protrudes through the mica support 20 While the control grid support rods .23 and the screen grid support rods 24 would similarly protrude. A suppressor grid 25 would be mounted by virtue of the insertion of tabs 26 in corresponding apertures in the mica supports 20 and 21. A portion of anode 27 is similarly supported by the cooperative engagement of tabs 28 in corresponding apertures of the respective mica supports. Apertures 29 are provided in the top mica support 20 and the bottom mica support 21 to receive and engage tabs 17 extending from the top and bottom edges respectively of main element 13' of the anode member portion it).

Electron discharge device 12, which, in the illustrative embodiment is shown as a dual-control pentode, similarly comprises a plurality of electrodes mounted between mica supports 30 and 31. The upper end of cathode 32 is shown extending through mica support 30'. First control grid support rods 33, screen grid support rods 34, and second control grid support rods 35 similarly protrude s eep/1e a, is through the upper mica 3t. A shield 3'7 completely envelops the electrodes of device 12 and is supported by virtue of the engagement of tabs 33 in corresponding slots in mica segments 3% and 31. An anode (not shown) is adapted to be supported between the shield 37 and second control grid, and is secured to the micas as by tabs 36. Apertures 469 are provided in mica supports 30 and 31 for receiving and engaging cars 18 extending from the top and bottom edges respectively of flanges lid and 15 of member lit.

Electron discharge device 111 and electron discharge device 12 are combined into a rigid integral unit, in accordance with the invention, by means of the metallic member it).

In assembling the device 11, the cathode 22, grids 24, 25 and anode portion 2-? are preliminarily oriented by insertion of the lower tabs or portions thereof into corresponding apertures of the lower mica 2i. Anode portion 16 is thereafter positioned by insertion of the lower tabs 17 thereof into openings 29 of the lower mica 21. Thereafter, the upper mica 2% is positioned by force fitting the upper tabs or portions of the respective electrodes through corresponding openings therein. In addition, to more firmly unite member 1t) and anode portion 27, a bond, which may be effected by spot welding, staking or other suitable means, may be formed between the shoulders 42 of anode 2'7 and the corresponding area of main element 13 in contact therewith.

After assembly of device it, electron discharge device 12 is mounnted on member Ml simply by insertion of cars 18, extending from the top of flanges Ji l and 15, into corresponding apertures all, in the top insulative support of electron discharge device 12, as illustrated in FIG. 2. Electron discharge device 12 can then be rotated toward the member using the upper ears 18 in apertures 4-1? as pivots. Upon contact of the ears 1%, extending from the bottom of flanges 1d and respectively, with bottom mica support 31, the camming action of the ears flexes the mica support downwardly until ears l8 engage apertures til, at which time the mica support snaps back into its normal position, locking ears 18 in apenures as of the bottom mica support. It will be noted that the leading edges of cars it; are provided with smooth arcuate surfaces to facilitate the camming action of insertion of ears 18 into apertures 4d, Also, the trailing edges are straight sided and preferably perpendicular to the lower edge of the flanges and lib, to ensure tight-locking fit oi the ears 18 after insertion into apertures 40).

Thus, electron discharge devices ill and 12 are firmly attached to member lid to form a rigid integral unit. Mica segments 2d, 21 and 3d, 31 are shaped so that upon attachment of the electron discharge devices to member til, the periphery of the adjacent mica segments corresponds generally to the shape of the inside wall of the tube envelope. Triangularly formed snubbers 43, extending from the peripheryof mica segments 2d, 21, 3t? and 3 11., contact the inner walls of the envelope to provide lateral support for the mount assembly within the envelope.

While I have hereinabove described the anode of the device 11 as being formed of two parts it? and 27, which are adapted to be assembled, in situ, it will be appreciated that the anode of device 11 may be preliminarily assembled as an integral anode by staking the main portion 13 of member ill to corresponding shoulder portions 42 of anode portion 27 as shown in FIG. 3. With such integral anode, assembly of the device 11 would be eliected by telescopically slipping the staked anode portions over coaxially aligned cathode and grids before the upper mica is positioned; Then, after the anode has been placed in position, the top mica 2t) would be slipped over the assembly to form the device Ill.

The mount assembly of the invention is not restricted to use with electron discharge devices of the same axial length, as shown in FIG. 1, but may be utilized to unite, into an integral unit, electron discharge devices of differ- Qil sat axial lengths. Thus, for example, if device 12 were of smaller length than device 11, the flanges 14 and 15 of member it) would be reduced in length by an amount corresponding to the ditierence in axial lengths of the devices it and 12, with no alteration in the height of the main portion of member iii. In this manner tabs 18 at the top of the foreshortened flanges l4 and 15, would still be adapted for insertion in corresponding openings of the upper mica 3t? of the reduced-size device 12. In all other respects assembly of the devices 11 and 12 would be as in the foregoing description.

FIG. 3 illustrates the preferred form of my invention with the mount assembly of the invention mounted within an evacuated tube envelope Snubbers 43 contact the interior wall of the envelope id to firmly secure the mica supports Ztl, 21, 3t and 31 and hence the electron discharge devices lll and 12 so as to render them laterally immovable. Leads 46 connect the various electrodes to the pin connectors 47 and serve to render the unit immovable axially within the envelope. The pin connectors 47 function to connect suitable sources of eneigizirx potential, not shown, to the electrodes.

Although the invention and its operation has been described with reference to a specific embodiment, it is intended that the invention is not limited to the particular details shown and described which may be varied without departing from the spirit and scope of the invention and the appended claims.

What I claim as new and desire to secure by Letter Patent of the United States is:

I. An electron tube mount assembly for devices in which a plurailty of electron discharge devices are en closed within a single envelope comprising:

(a) a first electron discharge device comprising (i) a first apcrtured top insulative support,

(2) a first apertured bottom insulative support,

(3) a plurality of electrodes supported between said top and said bottom insulative supports and maintained in spaced relation thereby, one of said electrodes having a main element, and a pair of side elements attached to said main element, at least one ear extending from each end of said main element and received in corresponding apertures of said top and said bottom supports, and at least one ear extending from each end of each of said pair of side elements, said ears being spaced from said top and said bottom sup orts and having a cam-like shape,

(b) a second electron discharge device comprising (1) a second apertured top insulative support,

(2) a second apertured bottom insulative support,

(3) a plurality of electrodes supported between said second top and said second bottom insulative supports and maintained in spaced relation thereby,

(4) apertures in said second top insulative sup port pivotally receiving the ears extending from corresponding ends of said pair of side elements of said one electrode, and

(5) apertures in said second bottom insulative support receiving in cam-like engagement therewith the ears extending from the other corresponding ends of said pair of side elements of said one electrode.

2. The electron tube mount assembly of claim 1 in which said one electrode is an anode and said main element is an active anode surface.

3. The electron tube mount assembly of claim it in which said first electron discharge device and said second electron discharge device are pentodes.

4. The electron tube mount assembly of claim 1 in which said ears of said side elements are formed with leading edges of arcuate shape to facilitate said cam-like engagement of said side-element ears and preselected apertures in said second bottom support.

5. An electron discharge tube incorporating a plurality of electron discharge devices, said tube comprising:

(a) a connecting member comprising a main element,

a pair of flanges,

a plurality of ears extending from the top and the bottom of each said main element and said flanges, the ears on said flanges having leading edges of arcuate shape (b)a first electron discharge device comprising a first and a second insulative support, one at each end thereof, and each having a plurality of slots receiving the said ears on the respective ends of said main element, and

(e) a second electron discharge device comprising a third and a fourth insulative support, one at each end thereof, and each having a plurality of slots, the said slots of said third insulative support pivotally receiving the ears at one end of said flanges and the slots devices.

References Iited by the Examiner UNITED STATES PATENTS Wolke et a1 313-6 Ruzinksy 3l31 Bloom et a1. 3133 Millis 313-1 Myford 3131 DAVID J. GALVIN, Primary Examiner.

JAMES D. KALLAM, Examiner. 

1. AN ELECTRON TUBE MOUNT ASSEMBLY FOR DEVICES IN WHICH A PLURALITY OF ELECTRON DISCHARGE DEVICES ARE ENCLOSED WITHIN A SINGLE ENVELOPE COMPRISING: (A) A FIRST ELECTRON DISCHARGE DEVICE COMPRISING (1) A FIRST APERTURED TOP INSULATIVE SUPPORT, (2) A FIRST APERTURED BOTTOM INSULATIVE SUPPORT, (3) A PLURALITY OF ELECTRODES SUPPORTED BETWEEN SAID TOP AND SAID BOTTOM INSULATIVE SUPPORTS AND MAINTAINED IN SPACED RELATION THEREBY, ONE OF SAID ELECTRODES HAVING A MAIN ELEMENT AND A PAIR OF SIDE ELEMENTS ATTACHED TO SAID MAIN ELEMENT, AT LEAST ONE EAR EXTENDING FROM EACH END OF SAID MAIN ELEMENT AND RECEIVED IN CORRESPONDING APERTURES OF SAID TOP AND SAID BOTTOM SUPPORTS, AND AT LEAST ONE EAR EXTENDING FROM EACH END OF EACH OF SAID PAIR OF SIDE ELEMENTS, SAID EARS BEING SPACED FROM SAID TOP AND SAID BOTTOM SUPPORTS AND HAVING A CAM-LIKE SHAPE, (B) A SECOND ELECTRON DISCHARGE DEVICE COMPRISING (1) A SECOND APERTURED TOP INSULATIVE SUPPORT, (2) A SECOND APERTURED BOTTOM INSULATIVE SUPPORT, (3) A PLURALITY OF ELECTRODES SUPPORTED BETWEEN SAID SECOND TOP AND SAID SECOND BOTTOM INSULATIVE SUPPORTS AND MAINTAINED IN SPACED RELATION THEREBY, (4) APERTURES IN SAID SECOND TOP INSULATIVE SUPPORT PIVOTALLY RECEIVING THE EARS EXTENDING FROM CORRESPONDING ENDS OF SAID PAIR OF SIDE ELEMENTS OF SAID ONE ELECTRODE, AND (5) APERTURES IN SAID SECOND BOTTOM INSULATIVE SUPPORT RECEIVING IN CAM-LIKE ENGAGEMENT THEREWITH THE EARS EXTENDING FROM THE OTHER CORRESPONDING ENDS OF SAID PAIR OF SIDE ELEMENTS OF SAID ONE ELECTRODE. 